Share Repurchases (Narrative) (Details) - March 2017 Program [Member] $ in Millions	Jan. 31, 2021 USD ($)
Statement [Line Items]
Authorized amount for shares repurchase	$ 1,500
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 1,296

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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